Roger Federer takes on Rafael Nadal in one of the most eagerly awaited group stage matches at the ATP World Tour Finals.
You can watch and bet on Federer v Nadal from 20.00 GMT Tuesday live for free at bet365 > live tennis
For all his success against the Swiss, Nadal has never beaten his great rival at the ATP World Tour Finals. They met in the semi-finals in 2006 and 2007 on a fairly fast indoor court in Shanghai with Federer's superb serving seeing him ease to straight sets wins each time. And of course they contested last year's final at the O2 Arena where Federer produced one of his best ever indoor performances to see off the Spaniard in three sets.
This one will be interesting as if Nadal loses again it leaves him with a potentially tricky decider against Jo-Wilfried Tsonga to try qualify for the semi-finals. Neither player looked particularly impressive in their opening matches, showing just flashes of their best.
Federer suffered a dramatic concentration lapse against Tsonga and was slightly fortunate that the Frenchman threw in such a dire service game at a decisive point in the match. And if Mardy Fish hadn't tightened up when he broke to go 3-2 up in the third set on Sunday night, Nadal could have easily lost.
The surface is slightly slower this year which will definitely help the Spaniard from the back of the court but he was constantly guilty of dropping the ball short against Fish and Federer will not be so generous.
Expect a close one but Federer to win this in three.
